Belly dumps, also known as bottom dumps, or semi-bottom dumps, are trailers that are towed by a truck and used for the delivery of aggregate materials from the trailers through one or more openings (called “gates”). Belly dump trailers are a useful tool on the jobsite because they carry a larger payload than a standard dump truck, they can be unloaded faster than a transfer rig, and they are safer than an end dump trailer. One very useful advantage that a belly dump trailer has on a jobsite is that it has the capability of “windrowing” its cargo. This is especially advantageous during a grading operation or for paving purposes.
During a grading or paving operation, the windrow is set at a proper size to accommodate the work being done. Windrows that are too heavy or too light have a dramatic effect on productivity for the grading or paving crew.
FIGS. 1, 2A and 2B illustrate the way that most of the current trailers control the windrow size. Although there are trailers that employ a “pin” or manual “stop” system, they all require the driver to manually set them each time the trailer dumps. The reason that resetting the stops or chains each trip is necessary is that, with the gates not fully open, some of the cargo will sit on the gates inside the trailer and not get dumped out. This means that the cargo gets hauled back to the source and, whether paying by volume or weight, gets purchased again. To avoid this from happening, the stops or chains must be removed each time so that the gates can be fully opened to empty all cargo.
Currently, the driver of the vehicle must stop the truck, exit the driver's seat and cab of the truck, manually set a series of chains that will retain the gates at a width determined by the length of the chain, re-enter the cab of the truck, spread the cargo, close the gates, exit the truck again and remove the chains, and finally, re-enter the cab of the truck and open the gates to a full open position to empty all of the remaining cargo. Now the gates can be closed for another load. Another method to control the spread is to have a person walk along beside the trailer and manually operate a remote valve that is mounted on the trailer and watch the spread making necessary adjustments. This is a very difficult way to get any kind of consistency.
Some approaches to remote gate control are known, but these are understood to require operation of the gate from outside of the vehicle, such as via a corded connection to a handheld unit or via a wireless connection. Thus, these approaches still suffer from the drawbacks of requiring the driver to exit the vehicle each time the gate is moved, or to have another individual perform this function, which is not efficient. Also, it would be desirable to provide a safer alternative than requiring the driver or another person to be present in the in the immediate vicinity of the dumping operation, especially in the case of dumping operations carried out with moving vehicles. Further, none of the prior approaches appear to provide for consistent control of the extent of the gate opening to allow for repeatable results, both in successive dumping trips or by different vehicles.